Abstract. The TACTIC telescope is operational for more than ten years at GOALS observatory, Mt. Abu (24.6N, 72.7 E, 1300m AMSL). It is an imaging gamma-ray telescope based on the atmospheric Cherenkov technique, wherein a large light collector and a fine cluster of PMTs (camera) along with the relevant instrumentation are used to record images of Atmospheric Cherenkov Flashes (ACF), during clear and moonless nights. The ACF based very high energy gamma-ray telescopes require a suitable site characterized particularly by the maximum annual number of cloudless clear nights, with no artificial background light and low dust levels. In our earlier site characterization study before the TACTIC installation, it was found that the Mt Abu site offered more than 60% clear nights for TeV observations in a year. We have continued this study since 1999, using an automatic weather station, which was installed during the same year to collect data on various meteorological parameters. Results of the analysis of recorded data for atmospheric parameters like temperature, wind speed, dust load (Total Suspended Particulate Matter TSPM) and number of clear nights from 1999 to 2010 will be presented at the meeting.